Electrical arc welding



UNITED STATES PATENT OFFICE.

JACK CHURCHWABJ), OF NEW YORK, N. Y., ASSIGITOR '10 WILSON WELDER &METALS COMPANY, INC., A QORPORATION OF NEW YORK.

ELECTRICAL ABC WELDING.

1,423,914. No Drawing. implication filed January To all whom it mayco'naern."

Be it known that I, JACK OHUnoHwARi), a

citizen of the United States, and "a resident of the city, county, andState ofNew York,

have invented. certain new and useful Imrovements in Electrical ArcWelding, of which the following is a specification.

My invention relates to an improved 5 duce a method of electric arcwelding in which the welding metal willbe deposited more rapidly,eflicientlyand cheaply.

Hitherto electric arc welding has been practiced according to twogeneral methods. In the first of these general methods, .the metal to bedeposited upon the work was supplied by the electrode which alsofurnished the heat to the are. This method, which has been called themetallic-arc method, I

when properlycarried out produced a very high grade of weld deposit,Unfortunately, however, it was necessary to use'an electrode of quitesmall cross-section because the higher amperage, which would benecessary to fuse a large electrode, would be detr1- mental to the weld.It will be evident, therefore, that with the metallic-arc method themetal necessarily was deposited comparatively slowly and, consequently,this method was limited in its application to weld operations not"necessitating rapid metallic de osit.

he second of the two general methods above mentioned was the so-calledcarbonarc method. In this method a carbonelectrode was employed forsupplying the necessary heat to the arc while the welding metal itselfwas fed to the are by means of a metal rod. The metal rod could be madeof any convenient shape and the size of the rod was dependent only. onthe speed of metallic deposit, which-could be made as' rapid as desired.In practicing the carbon-arc method it was found that a certain amountof carbon from the electrode entered the composition of the metallicweld deposit. This contamination with carbon was in many instancesdeleterious to the properties of the weld and was particularlydeleterious when welding low carbon steel for, as is.

well known, the addition of carbon to such Q I Specification of LettersPatent. Patented July 25, 192 2.

14, 1920, Serial No. 351,358. nenewea'rebruar 3, 1922. Serial No.533,931.

steel has a tendency to render it brittle and porous.

Y My invention aims to combine the advantages of the two general methodsabove vmentioned 'without any of the disadvantages.

Ihave discovered that the above objects and aims may be secured byemploying a tungsten electrode to supply the heat to the arc andfurnishing the metal either by a metallic rod or from the work itself.

One of the advantages of operating with a tungsten electrode is thatcontamination of the weld by carbon is entirely obviated. Tungsten, asis Well known, hasan exceed ingly high melting point (3200 C.) and,consequently, in the heat ofvthe arc the tungsten electrode does notmelt but merely oxidizes slowly, forming an oxide of tungsten. Thisoxide does notfinterfere with the welding and it has been found that itdoes notin any way injure the weld deposit.

One example of the many uses to which my invention may be put is in thefilling up of blow-holes in low carbon steel castings. Thisoperationoften requires a lar e mass of metal to be deposited,particularly Where the castings areof large size. The metallic-arcmethod has been found to be so slow and laborious that in many instancesit is extremely expensive to employ 1t for.

this Work and, hence, that method is practically unavailable, Thecarbon-arc method is also unavailable owing to the corn ciently filledup with metal,having all the required physical and chemical character--istics. While tungsten is more expensive than carbon for electrodes, ithas been found by experience that for this class of work it is cheaperto use, it on account of the more satisfactory results obtained. 1

Another important use to which my invention may'be put is in the rapidwelding of thin sheets of low carbon steel, as for example the, seams'ofthin steel tubes. In welding such metal sheets, it has been.

found that no metal rodis necessary for the reason that the weldingmetal is entirely supplied by the thinsheets themselves, the

heat ofthe are being sufficient to the I edges of the sheets and weldthe same. .If-a

composed of tun'gs 7 will carbon electrode were used for such work, themetal at the joint would become badly contaminated with carbon, causingthe same to be brittle and porous. By my new method of welding with atungsten electrode,

however, a is obtained.

Another example of the use of my invention is in the cutting of metalsby the electric are where it is desired to positively preventcarbonization of the'metal by the electrode.

It will be obvious, therefore, that my new method of Welding combinesthe purity of deposit characteristic of the metallic-arc method with therapidity of operation characteristic of the carbon-arc method.

I desire it to be understood that my invention is'not limited to thespecific examples herein disclosed, but may be practiced in variousother ways within the scopeof the following claims.

durable, strong and ductile joint Having fully described my invention,what I c aim as new and desire to secure by Letters Patent is:

1. An electrode for electric arc welding ten.

2. An electrode for welding steel by the electric arc methodcomposedessentially of tungsten. 'j

3. An electrode for electric arc Welding for supplying heat only to thearc, said electrode being composed of a metal which not carbonizeithemetal passing through the'arc.

' 4. An electrode forwelding steel by the 7. A method of improving thecharacter welds produced by the electric arc method, which comprisessupplying heat to the are from an electrode of an inert metal andsupplying welding metal to the arc.

8. A method of improving the character of Welds produced by the electricarc method, which comprises supplying heat to the are from an electrodeof inert metal free from carbon and supplying welding metal to the are.

9 A method of carrying out an electric welding operation to prevent theintroduction of carbon into the weld, which comprises supplying the heatto'the are from an electrode of inert refractory metal which will notproduce carbon'dioxide at the temperature of the arc.

In testimony whereof, I have affixed'my signature to this specification.

J AGK OHURGHWARD;

